B2345
DTC B2345
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC B2345 0B
- Front Seat Heater Disable Circuit
DTC B2345 13
- Front Seat Heater Temperature Above Threshold
DTC B2345 42
- Front Seat Heater Current Sensing Calibration Data Not Present
DTC B2345 4B
- Front Seat Heater Current Sensing Calibration Data Out of Range
Diagnostic Fault Information
Circuit/System Description
The driver and front passenger heated seat heating elements are controlled by a common high current relay internal to the memory seat module (MSM) and the low side by individual element control circuits. The MSM connects the heated seat heater element supply voltage circuits for both seats to a common reference point. This reference point is biased to approximately 2.0 volts. Before the memory seat module will allow heated seat operation, it checks to see if this reference voltage is shorted to ground or battery voltage. Once the module verifies that it is not closing to a shorted heating element, it allows heated seat operation. After which it continues to monitor for a shorted circuit.
Conditions for Running the DTC
The memory seat module must be powered.
Conditions for Setting the DTC
B2345 0B
After a heated seat is activated, the MSM detects a shorted circuit on the seat heating element supply voltage circuit or control circuit.
B2345 13
Any of the temperature sensor inputs remains less than 1.5 volts for a seat back or 0.95 volts for a seat cushion for more than 1 second.
B2345 42
This DTC will set if the MSM calibration is not programmed.
B2345 4B
This DTC will set if the MSM calibration is out of range.
Action Taken When the DTC Sets
The heated seat functions for both front seats will be disabled.
Conditions for Clearing the DTC
* The current DTC clears when the malfunction is no longer present and the power mode changes to OFF then back to ACC or RUN.
* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.
Circuit/System Testing
B2345 0B
1. Ignition OFF, disconnect the X1 and X4 harness connectors at the MSM.
2. Test for infinite resistance between the left seat heating element supply voltage circuit terminal 6 and ground.
^ If less than infinite, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to ground.
3. Ignition ON, verify that a test lamp does not illuminate between the supply voltage circuit terminal 6 and ground.
^ If the test lamp illuminates, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to voltage.
4. Test for infinite resistance between the right seat heating element supply voltage circuit terminal 14 and ground.
^ If less than infinite, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to ground.
5. Ignition ON, verify that a test lamp does not illuminate between the supply voltage circuit terminal 14 and ground.
^ If the test lamp illuminates, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to voltage.
6. If all circuits test normal, replace the MSM.
B2345 13
1. Ignition OFF, disconnect the X2 and X5 harness connectors at the MSM.
2. Ignition OFF, test for greater than 15 ohms between the following seat cushion temperature sensor signal circuits and the low reference circuits:
* Driver seat cushion terminal 1 X5 and terminal 3 X2
* Passenger seat cushion terminal 2 X5 and terminal 6 X2
^ If less than the specified value, test for a short between the signal and low reference circuits. If the circuits test normal, replace the appropriate temperature sensor.
3. Test for greater than 15 ohms between the following seat back temperature sensor signal circuits and the low reference circuits:
* Driver seat back terminal 4 X5 and terminal 2 X2
* Passenger seat back terminal 3 X5 and terminal 6 X2
^ If less than the specified value, test for a short between the signal and low reference circuits. If the circuits test normal, replace the appropriate temperature sensor.
4. If all circuits test normal, replace the MSM.
B2345 42 or B2345 4B
If either DTC is set, replace the MSM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
* Driver Seat Back Cushion Heater and Passenger Seat Back Cushion Heater Replacement
* Driver Seat Cushion Heater and Passenger Seat Cushion Heater Replacement (Driver) Driver Seat Cushion Heater and Passenger Seat Cushion Heater Replacement (Passenger)